Where do i start?

[saridout]

I just got my baby back from the body shop, and it's beautiful, but after 7 months of not driving it, i was given a strong reminder of just how rough it rides and steers. I know now that i should have done the suspension before the body, but this is my first project and i'm learning along the way.

What i'd like to know is, where do i go from here? I don't want (and can't afford) anything really fancy, i just want it to feel smoother. There's a lot of vibration in the front of the car, and the steering wheel shakes like mad when i get up to about 60mph. i got a poly bushing kit and i replaced the steering rack bushings and the column coupler, but that didn't change anything, it still shakes. The strange thing is, the shaking is sort of intermittent. Most of the time, at high speed, it shakes badly enough to make my arms numb, but then occasionally, it will barely shake at all. I thought at first that it was just from driving on different surfaces, but then i noted the intermittence while on the same stretch of highway. Thoughts?

Either way, what's the first thing i should do on a suspension that hasn't ever been touched?

Edited October 7, 2010 by saridout

[Zed Head]

I had a slight steering wheel shimmy that went away after I tightened the wheel bearings.

[Zs-ondabrain]

Tie rod ends, take the tires in to make sure they have a true ballance on them, Struts (KYB for a stock stance) That's for starters. The rubber steering coupler will reduce some feel in the steering wheel, where as the urethane coupler will increase the amount of vibration you feel.

Dave

[Zforce]

Try rotating your tires and see if the problem goes away, also check your front wheel bearings, they could be loose. One of your wheels could be bent too.

[mgood]

I had a shimmy in the font end for 30 years, it was a bent aluminum wheel I bent when I hit a pot hole bad enough to blow the tire. That also caused the outer race on the outer bearing to start to slip and cause the hub to grind away, I had to get a new hub and bearings for that side. At the time the dealer said it was a bent strut axle so I replaced that. That was not it, I found the slipping outer race myself. I also moved the bent wheel to the back and all is well now.

[Z Speed]

Badly warn or spotted tires will cause this effect too. Just a thought. Start with the easiest and move your way forward....

[saridout]

thanks for the suggestions yall. i guess my first stop will be the tire shop. i'll let you know what comes of it

[mlc240z]

If they are relatively new tires or you're getting a new set, make sure they speed balance them.

Vibrations at different speed also indicates unbalanced tires.

[ta240]

when I bought my current Z it had the KYB GR2 cartridges in the struts. Replaced them with Tokicos. The Tokicos handle better but I often miss the ride the GR2s had. It was much smoother with them.

Fought a shimmy like that for years on my old Z. Replaced all the suspension components, wheels, tires, steering rack. Never completely went away and it was also somewhat intermittent which really drove me nuts.

As mentioned make sure the wheel bearings are tight enough, get the tires balanced on a road-force balancer. These cars seem to be really sensitive to wheel balance and some tire shops just aren't that good at it.

On my old Z each bushing I 'upgraded' to urathane tended to just deliver more of the shake to the steering wheel.

Edited October 7, 2010 by ta240

[Zs-ondabrain]

Now that you have a picture on the first post, I can tell you what the prolem is. Somebody, probably the Previous owner, bolted a "Park Bench" on your front end....

Sorry, couldn't help it.

Dave

[mlc240z]

Dave, Heel!

LOLLOLLOL

[Zs-ondabrain]

Arff Arff. I'm sure he knows I'm just messing with him.